172例乳腺浸润性癌 HER -2免疫组化与 FISH 技术检验对比研究

目的：比较免疫组化（IHC）和荧光原位杂交（FISH）技术在检测乳腺浸润性癌患者中 HER -2蛋白表达和基因扩增的一致性。方法：分别用 IHC 和 FISH 技术对172例乳腺浸润性癌 HER -2进行蛋白表达和基因扩增检测,比较两者检测的结果和相关性。结果：172例浸润性乳腺癌标本行 IHC 检测结果30例为（1＋）,88例为（2＋）,42例为（3＋）,12例为（-）。172例乳腺癌标本进行 FISH 检测结果71例为阳性,101例为阴性。其中 FISH 结果阳性标本中 IHC 检测有2例（1＋）,30例（2＋）,39例（3＋）。IHC 检测 HER -2为（3＋）的病例 FISH 检测中阳性符合率92.9%（39/42）,且检测 HER -2（-）的病例 FISH 检测均为阴性, IHC 检测 HER -2（2＋）的88例患者中有58例经 FISH 检测证实 HER -2呈阴性,30例呈阳性。FISH 检测共发现47例17号染色体多体,其发生率为27.3%。用 IHC 检测 HER -2发现有25例标本存在肿瘤之间的不同表达,而在这25例标本的 FISH 检测结果中有11例存在 HER -2基因瘤内遗传异质性。结论：HER -2蛋白表达和基因扩增 IHC 和 FISH 检测在免疫组化强阳性的标本中具有较好的一致性,且免疫组化染色强度与HER -2基因扩增呈正相关。理解和判断 HER -2基因遗传异质性对肿瘤药物应用及 HER -2基因检测方法具有指导意义。     

乳腺癌HER2基因扩增的临床病理意义

目的 检测乳腺癌组织中HER2基因扩增状态,评价其临床病理意义。方法 应用FISH、IHC方法分析55例乳腺癌HER2基因扩增/蛋白表达状态与临床病理特征的关系,比对IHC法与FISH检测的一致性程度。结果 55例乳腺癌FISH检测有32例（58.2%）HER2基因扩增。IHC法HER2（+++）22例中21例（95.5%）HER2基因扩增;HER2（++）12例中10例（83.3%）HER2基因扩增;HER2（+/－）21例中1例（4.7%）HER2基因扩增。39例浸润性导管癌中30例（76.9%）有HER2基因扩增,12例浸润性小叶癌中仅1例（8.3%）HER2基因扩增。HER2基因扩增在浸润性导管癌的组织学分级间差异有统计学意义（P<0.001）,组织学Ⅲ级的浸润性导管癌较Ⅰ、Ⅱ级有较高的HER2基因扩增率。HER2基因扩增与ER、PR阴性状态及腋淋巴结转移有显著相关性（P<0.01）,与患者是否绝经无相关性（P>0.05）。结论 浸润性小叶癌,ER、PR阳性以及组织学Ⅰ级的浸润性导管癌常少有HER2基因扩增;对于组织学Ⅲ的浸润性导管癌,同时ER、PR阴性者尽管IHC检测结果为阴性,仍需做FISH检测以明确是否有HER2基因扩增。     

IHC、FISH与CISH检测乳腺癌Her-2基因状态的对比研究

目的 比较免疫组织化学法(IHC)、荧光原位杂交法(FISH)与显色原位杂交法(CISH)检测乳腺癌HER2基因状态的一致性,探讨FISH法与CISH法榆测乳腺癌HER2基因状态的临床意义.方法 对64例乳腺浸润性导管癌石蜡标本分别应用IHC法、CISH法与FISH法检测HER2蛋白、HER2基因状态及17号染色体多体的发生率.结果 HER2蛋白表达(+++)组,IHC与CISH、FISH法检测HER2基因扩增阳性的符合率均为100%;HER2蛋白表达(++)组,IHC与CISH、FISH法检测的符合率分别为95.83%与91.67%;HER2蛋白表达(+/-)组,IHC与CISH、FISH法检测的符合率亦均为100%.FISH法与CISH法的检测结果1例存在差异,FISH法与CISH法检测HER2基凶状态总的符合率为98.41%.17号染色体多体的发生率在IHC(+++、++、+/-)三组中分别为45.16%、45.83%和11.11%,其总的发生率为40.62%.结论 IHC法柃测HER2蛋白仅作为初筛方法;FISH法与CISH法检测HER2基因状态存在较高程度的符合率,CISH法可作为一种更加方便可行的方法检测HER2基凶状态;在疑有17号染色体多体干扰时,应进一步行FISH法检测.     

EGFR、HER2 在食管鳞癌中的状态及临床意义研究

目的：探讨食管鳞癌中EGFR信号传导通路相关分子EGFR、HER2的表达情况及二者之间的相互关系,对比研究免疫组织化学方法（IHC）检测食管鳞癌HER2蛋白表达和荧光原位杂交技术（FISH）检测HER2基因状态的一致性。方法：随机选取食管鳞癌根治术后的切除标本76例和21例癌旁正常鳞状上皮组织,应用IHC法检测EGFR的表达。IHC法及FISH法分别检测HER2蛋白表达和HER2基因状态,并进行对比分析。结果：EGFR在食管鳞癌的表达明显高于癌旁正常鳞状上皮（63．2％VS33．3％,P〈0．05）;HER2在食管鳞癌低表达（3．9％）,正常鳞状上皮不表达。EGFR、HER2表达均与脉管累犯、淋巴结转移正相关,此外,HER2表达还与肿瘤浸润深度正相关。HER2与EGFR表达未发现相关性;HER2蛋白为阳性的患者中,HER2基因扩增符合率为66．7％（2／3）。HER2蛋白为阴性的患者中,HER2基因非扩增符合率为100％（73／73）。两种方法检测结果比较差异无统计学意义（P〉0．05）。结论：EGFR在食管鳞癌中高表达可能与食管鳞癌的发生发展有关,并有可能成为靶向治疗的靶点,而HER2在食管鳞癌中由于表达很低,有可能不是该肿瘤分子治疗的靶点。IHC检测HER2蛋白与FISH检测HER2基因结果一致性较高。     

荧光原位杂交和免疫组织化学法检测乳腺浸润性导管癌中HER-2基因状态的研究

目的 比较荧光原位杂交（FISH）和免疫组织化学（IHC）两种方法检测乳腺浸润性导管癌人类表皮生长因子受体2（HER-2）基因扩增及与C-erbB-2蛋白表达结果的一致性。方法 分别采用FISH和IHC法检测346例乳腺浸润性导管癌组织HER-2基因扩增和C-erbB-2蛋白表达,并对两种方法的结果进行统计学分析。结果 346例乳腺浸润性导管癌中,FISH检测HER-2基因扩增145例（41.9％）,无扩增201例（58.1％）。IHC检测显示,C-erbB-2蛋白（-）7例,（+）30例,（++）227例,（+++）82例。按乳腺癌HER-2检测指南,（-）和（+）为阴性结果,（+++）为阳性结果,（++）为不确定病例。全组IHC检测C-erbB-2蛋白阳性表达率为23.7％（82／346）。IHC检测C-erbB-2蛋白（-）的7例患者经FISH检测无HER-2基因扩增,一致率为100.0％。IHC检测C-erbB-2蛋白（+）的30例经FISH检测25例无基因扩增,一致率为83.3％;227例（++）中有65例基因扩增,一致率为28.6％;82例（+++）中有基因扩增75例,一致率为91.5％。IHC和FISH检测HER-2状态的一致率为89.9％,具有高度一致性（Kappa值=0.768,P＜0.001）。HER-2基因扩增与年龄、肿瘤大小、组织学分级及淋巴结转移均无关（P＞0.05）。结论IHC和FISH法检测乳腺浸润性导管癌HER-2表达状态有高度一致性。IHC可以作为初步筛查乳腺浸润性导管癌HER-2基因状态的首选检测方法,对于IHC检测结果为（++）的标本建议采用FISH法进一步明确HER-2基因扩增状态。     

IHC和FISH检测乳腺癌HER-2表达的对比研究

目的:比较免疫组化(IHC)和荧光原位杂交(FISH)技术在检测乳腺浸润性癌患者中HER-2蛋白表达和基因扩增的一致性。方法:分别选用IHC和FISH技术对102例乳腺浸润性癌HER-2进行蛋白表达和基因扩增检测,比较两者检测的结果和相关性。结果:102例浸润性乳腺癌标本中FISH阳性55例,阴性47例。IHC检测0、1+、2+和3+的FISH阳性符合率分别为0(0/6)、9.52%(2/21)、65.00%(39/60)和93.33%(14/15)。IHC检测HER-2为2+/3+的标本中70.67%(53/75)显示HER-2基因扩增,1+/0患者中7.50%(2/27)显示HER-2基因扩增,Kappa系数为0.511,P<0.01。FISH检测结果显示,17号染色体多体总发生率为11.76%(12/102),在HER-2高表达的患者中发生率为9.33%(7/75),无或低表达发生率为18.52%(5/27),χ2=1.614,P=0.204。结论:HER-2蛋白表达和基因扩增IHC和FISH检测方法有较高的符合率,一致性较好。17号染色体多体可能是造成2种方法结果差异原因之一。     

非小细胞肺癌EGFR荧光原位杂交与免疫组化检测的比较

目的探讨荧光原位杂交（FISH）技术和免疫组化（IHC）法检测石蜡标本非小细胞肺癌（NSCLC）EGFR基因扩增及蛋白表达水平的差异性。方法采用FISH和IHC分别检测27例NSCLC患者石蜡标本EGFR基因和蛋白表达,对2种方法的检测结果进行对比分析。结果 14例IHC法EGFR表达（3＋）的标本中有9例FISH显示阳性（64.29%）,其中5例为EGFR基因高多体性扩增（55.56%）,4例为EGFR基因扩增（44.44%）;6例IHC（2＋）的标本中仅1例为高多体性扩增（16.67%）;2例IHC（1＋）及5例IHC（-）标本均无EGFR基因扩增。结论 IHC法初筛（3＋）、（2＋）的标本与FISH检测的符合率较低,提示对IHC检测EGFR表达为（3＋）及（2＋）并选择靶向药物治疗的病例,应采用FISH法对EGFR基因表达作进一步检测。     

色素原位杂交在检测乳腺癌患者组织中HER2基因的应用

[目的]探讨色素原位杂交（CISH）在检测乳腺癌患者组织中HER2基因状态的临床应用，比较CISH与免疫组化（IHC）检测组织HER2状态的差异性。[方法]采用SPOT—Light HER2 CISH^TM试剂盒，以CISH方法对40例IHC EnVision法染色分别为（＋＋＋）、（＋＋）、（＋）和阴性（-）的乳腺癌石蜡切片标本进行HER2基因状态的检测。[结果]HER2表达IHC（＋＋＋）的8例标本中，7例为HER2基因扩增CISH检测，1例无扩增；（＋＋）的13例标本中，5例为HER2基因扩增．8例无扩增；（＋）的10例标本中，2例为HER2基因扩增，7例无扩增；（-）的9例标本均无扩增。两种方法对乳腺癌组织HER-2／neu状态的检测有一定的差异性（kappa=0．458，P=0．003）。[结论]IHC是HER表达初步筛查的首选方法，由于蛋白表达和基因扩增检测结果存在一定的差异性，建议IHCC（＋＋＋～＋）患者进一步作CISH检测确诊。     

应用荧光原位杂交法检测乳腺癌石腊样本中HER-2 基因的扩增

 目的 探讨荧光原位杂交法（Fluorescence in situ hybridization，FISH）检测乳腺癌HER-2基因扩增在临床病理诊断及分子靶向治疗中应用的可能性。方法 用FISH技术和免疫组化（Immunohisto—chemistry，IHC）技术检测50例乳腺导管癌石蜡包埋标本并比较两种方法的结果以及与临床病理的关系。结果 16／50例HER-2蛋白表达阳性，其中强阳性5例，中度阳性9例，弱阳性2例；11／50（22％）例乳腺癌标本FISH技术检测HER-2基因扩增阳性，其中5／5为免疫组化HER-2蛋白强阳性病例；6／9为中度阳性病例，其中1例为17号染色体多倍体与HER-2基因扩增。HER-2基因扩增与蛋白表达与乳腺癌转移有关（P〈0．05）。结论 FISH技术可稳定地检测用IHC确定的HER-2蛋白阳性乳腺癌中HER-2基因的扩增状况，并用于临床赫赛汀分子靶向治疗病例的筛选。     

色素原位杂交法和免疫组织化学法检测乳腺癌HER-2基因扩增及蛋白表达

目的:对照色素原位杂交法(chromogenic in situ hybridization,CISH)和免疫组织化学法(immuno-histochemistry,IHC)检测乳腺癌组织中人表皮生长因子受体(human epidermal growth factor receptor-2,HER-2)基因扩增及其蛋白表达的状况.方法:采用CISH技术检测145例乳腺癌组织中HER-2的基因扩增情况,其中14例标本经过荧光原位杂交(fluorescence in si-tu hybridization,FISH)检测,随后分别用FISH和IHC方法检测的HER-2基因扩增及蛋白表达状况与之进行回顾性对照,并按照病理分级、淋巴结状态、绝经与否和雌激素受体(estrogen receptor,ER)/孕激素受体(progesterone receptor,PR)表达情况进行分层,分析HER-2表达与乳腺癌各高危因素之间的关系.结果:CISH检测发现,HER-2无扩增71例(50.0%),低扩增11例(7.6%),高扩增63例(43.4%).14例FISH与CISH检测结果比较,符合率为100.0%.145例IHC与CISH检测结果的符合率为84.8%(P<0.05).在IHC检测积分为0/ 以及 的病例中,HER-2基因扩增与蛋白表达情况基本一致,其符合率均在90%以上;而在IHC检测积分为 的标本中,HER-2基因扩增率仅为61.1%.CISH及IHC检测均显示ER/PR表达情况与HER-2阳性呈负相关,ER和PR均为阴性患者的HER-2基因扩增率和蛋白表达率明显高于ER/PR阳性的患者(CISH:68.3%vs 38.8%,P<0.01;IHC:71.7%vs 48.2%,P<0.01).HER-2状态与乳腺癌病理分级、腋淋巴结转移以及绝经与否无关(P>0.05).结论:CISH技术检测HER-2操作简便,准确性高,可以代替FISH技术,对IHC评分为 的病例应进一步确认HER-2状态.HER-2除了与ER/PR表达相关外,与其他乳腺癌高危因素无关,可作为独立指标进行检测.     

Prognostic utility of fluorescence in situ hybridization for determining HER2 gene amplification in breast cancer

An accurate investigation of the HER2 proto-oncogene is extremely important for the therapy and prognostication of breast cancer. Currently, immunohistochemistry (IHC) and fluorescence in situ hybridization (FISH) are standard methods for this purpose. The aim of this study was to detect the expression and amplification of HER2 in paraffin-embedded samples of breast cancer tissue and to investigate the relationship between HER2 amplification and various clinicopathological parameters in advanced breast cancers. We used FISH to examine the HER2 gene amplification and IHC to examine the expression of HER2 protein, estrogen receptor (ER) and progesterone receptor (PR) in 62 advanced breast cancers. HER2 gene amplification was detected by FISH in 12 breast cancers (19%) and HER2 protein expression with a score of 3+ was detected by IHC in 11 (17%). There was a significant correlation between the HER2 gene amplification and HER2 protein overexpression in breast cancers (P<0.0001). However, some mismatching was evident: 3 cases, negative for the HER2 gene, showed a HER2 protein expression score of 3+ and 2 cases, positive for HER2 gene amplification, had HER2 protein expression scores of 0 and 1+ (negative), respectively. ER and PR were expressed in 41 (66%) and 46 (74%) cancers, respectively. No correlation was observed between the HER2 gene amplification and any of the clinicopathological parameters examined, including age, histopathological type, TNM stage, tumor size, lymph node status, relapse and expression of PR. We observed three patterns among the 6 deceased cases: i) triple negativity for HER2, ER and PR, ii) positivity for HER2 gene amplification with a mismatching HER2 protein expression, and iii) positivity for the HER2 gene amplification with a matching HER2 protein expression score of 2+ or 3+. The triple negative cases and HER2 gene amplification positive cases with a mismatching HER2 protein expression had a poor outcome. These results suggest that in breast cancer, the detection of HER2 gene amplification by FISH is desirable compared with the HER2 protein expression determined by IHC. Moreover, triple negativity for HER2, ER and PR is a potentially very important prognostic marker.     

Status of HER2 amplification, polysomy 17 and histopathological features of 425 Pakistani breast cancer patients

HER2 gene amplification in invasive breast cancer is a robust predictive marker for response to transtuzumab therapy. This study was undertaken to measure concordance between immunohistochemistry (IHC) and FISH for HER2 gene amplification in invasive breast tumors, as well as the presence of polysomy 17 and possible correlation with demographics and histopathological variables, including ER and PR positivity. A total of 425 cases of infiltrating carcinoma of breast (99% IDC-NOS) were studied. HER2 over expression was tested by IHC and FISH methods. Association between IHC and FISH in both subsets was calculated by amplification ratio including polysomy 17. Out of 425 specimens, 128 (30%) were positive for HER2 amplification by FISH test, whereas only 78 (24%) tumors with 2+ expression showed amplification. In contrast, 39 (74%) demonstrated 3+ IHC score and HER2 gene amplification. The histological variables including tumor size, tumor type, and lymph node involvement did not influence the outcome of FISH analysis. The ER and PR status showed significantly greater positivity in patients negative for HER2 amplification. Polysomy 17 was detected in 23.7% patients and was positively associated with ER and PR expression (P= <0.05). Our study showed a concordance of 24% between 2+ IHC and FISH amplification, while in 3+ IHC cases the concordance was 74%. Significant links of HER2 amplification was seen with ER andPR negativity and higher tumor grade. In addition, non-significant correlations were noted with other variables like tumor type, size and lymph node status.     

乳腺癌组织TOP2A和HER2/neu扩增与临床病理因素相关性研究

目的 拓扑异构酶Ⅱ(typeⅡtopoisomerase,TOP2A) DNA是常见的化疗疗效预测因子,HER2是与乳腺癌相关的重要的原癌基因之一.本研究探讨乳腺癌组织中人类表皮生长因子受体HER2/neu和TopoⅡ之间的关系,及其与临床病理因素之间的相关性.方法 收集广西医科大学附属肿瘤医院2010-02-01-2012-09-30手术治疗的96例乳腺浸润性导管癌标本,实时定量聚合酶链式反应(real time polymerase chainreaction,RQ-PCR)检测和评估基因扩增水平,免疫组织化学(immunohistochemistry,IHC)微阵列(n=76)检查基因扩增和蛋白质表达水平之间是否存在相互关系.结果 根据RQ-PCR或IHC微阵列取得的HER2/neu基因状态,TOP2A基因的扩增水平差异无统计学意义,P值分别为0.481和0.935.在HER2/neu(-)基因型患者中,29.1％(14/48)的患者显示出TOP2A基因水平高于第三四分位值,然而22.9％(11/48)的HER2/neu(+)基因型患者的数值处于第一四分位值(log TOP2A＜0.62),因此表明存在低水平的扩增.采用IHC以及荧光原位杂交(fluorescence in situ hybridization,FISH)方法确定具有HER2/neu-基因型的60例患者中,22.9％(11/48)的患者在IHC微阵列上被归类为TOP2A(+)基因型患者.同时,采用IHC以及FISH法将患者视为HER2/neu(+)基因型患者的14例患者中,大多数患者(n=10)被归类为TOP2A(+)基因型患者.结论 乳腺癌组织中TOP2A基因的扩增并不局限于带有HER2/neu(+)基因型的患者,并且很大比例的HER2/neu(-)基因型患者表现出具有高水平的TOP2A基因.     

HER2 amplification ratios by fluorescence in situ hybridization and correlation with immunohistochemistry in a cohort of 6556 breast cancer tissues

To analyze HER2 amplification in a large cohort of diagnostic breast cancer specimens, fluorescence in situ hybridization (FISH) and immunohistochemistry (IHC) were performed on the same specimens with use of Food and Drug Administration&approved products. Procedures were standardized following the manufacturers' recommendations. Of 116,736 IHC specimens, 20% were positive for HER2. In 16,092 FISH specimens, 22.7% showed HER2 amplification. In the subset of 6556 tissues analyzed with IHC and FISH, however, 59% were positive on IHC and 23.6% were amplified on FISH. The increased frequency of positive test results is skewed by more frequent reflex FISH testing. In general, expression and amplification trended together, with the least amplification (4.1%) seen in IHC-negative cases, 7.4% amplification seen in IHC 1+ cases, 23.3% amplification seen in IHC 2+ cases, and 91.7% amplification seen in IHC 3+ cases. When FISH amplification ratios were stratified, the low FISH ratios (2.0-2.2) were most frequently seen in specimens with negative IHC results, high ratios (>5.0) were seen in IHC 3+ specimens, and intermediate levels of amplification were similar for all levels of IHC. The effect of changing the cutoff point was analyzed: removing cases with a ratio of exactly 2.0 decreased the FISH positivity rate to 22.2% in the combined IHC and FISH cohort. Sequentially moving the cutoff point to 2.2 and 2.5 affected cases at all IHC expression levels. Each change removed approximately 2% from the apparent positivity. This large database provides the distribution frequency of HER2 protein expression and gene amplification in invasive ductal and lobular breast cancer. The relationship between level of HER2 amplification and clinical outcome will require reanalysis of pivotal trial data.     

荧光原位杂交检测乳腺癌HER2（++）扩增状态及其与临床病理的相关性

目的 使用荧光原位杂交（fluorescence in situ hybridization, FISH）检测HER2基因扩增情况,并探讨影响HER2基因扩增的因素及其与临床病理特征的关系。方法 收集新疆医科大学附属肿瘤医院2013年l月至2015年12月间IHC检测HER2（++）的乳腺癌病例325份,均采用IHC和FISH两种方法分别检测所有患者的石蜡标本HER2表达和扩增情况,并分析HER2扩增状态与患者各临床病理特征的关系。结果 全组患者经IHC检测HER2表达均为（++）,FISH检测HER2扩增率为12.9%（42/325）,对12项临床和病理指标进行单因素分析显示：HER2扩增状态与激素状态、肿瘤直径、P53显著相关（P<0.05）,而与ki67表达、组织学分级、肿瘤个数等因素均无关（P>0.05）。结论 雌孕激素表达均阴性、肿瘤直径>2 cm、P53表达阳性是预测FISH检测IHC HER2（++）扩增的独立因素。     

荧光原位杂交和免疫组织化学方法检测乳腺癌组织中人类表皮生长因子受体2基因状态差异及其特征分析

目的比较荧光原位杂交(fluorescence in situ hybridization,FISH)和免疫组织化学(immunohistochemistry,IHC)检测乳腺癌组织中人类表皮生长因子受体2(human epidermal growth factor receptor 2,HER-2)基因状态差异,分析其相关特征。方法回顾性收集51例中山大学附属第三医院2007年10月至2008年9月间乳腺浸润性导管癌组织标本和相关信息,分别采用IHC和FISH法检测HER-2蛋白表达情况和基因扩增状态,比较两种方法的结果差异,用Fisher精确概率检验分析这种差异的相关因素。结果在51例标本中,FISH检测乳腺癌组织中HER-2基因阴性32例(62.75%,32/51),阳性19例(37.25%,19/51);IHC检测乳腺癌组织中HER-2为(-)和(+)者的FISH检测均为阴性(21例);12例IHC检测HER-2为(++),其中3例FISH检测为阳性,其余9例FISH检测为阴性;18例IHC检测HER-2为(+++)者仍有2例FISH检测结果阴性。月经状态和雌激素受体(ER)表达与IHC检测HER-2阳性病例的FISH阳性结果具有显著联系(P值分别为0.023和0.007),即在IHC检测HER-2阳性[(++)和(+++)]的病例中,绝经前女性较绝经期女性以及ER阴性者较阳性者更可能为FISHHER-2阳性(有HER-2基因扩增)。结论本研究的结果有助于提高IHC判断HER-2基因扩增的准确性。     

Concordant HER2 status between metastatic breast cancer cells in CSF and primary breast cancer tissue

It is not known whether the HER2 status of malignant CSF cells coincides with that of the original breast carcinoma cells. We investigated whether CSF cytology specimens were suitable to evaluate HER2 status by fluorescence in situ hybridization (FISH) in patient with leptomeningeal metastasis (LM). Both formalin-fixed paraffin-embedded (FFPE) breast cancer tissue and liquid based CSF cytology specimens were evaluated for HER2 status in 16 patients with LM. We evaluated HER2 gene amplification using FISH on destained CSF cytology slides containing a minimum of 20 malignant cells per slide, and compared these with the HER2 status by immunohistochemistry (IHC) or FISH in FFPE tissues. HER2 was considered positive when the HER2:CEP17 ratio was ≥2.0 or IHC 3+. Of 16 cases, four were HER2 positive and 12 were HER2 negative by FISH analysis in CSF cytology. All CSF-positive cases were HER2 positive by IHC in FFPE tissue. Of 12 HER2 FISH-negative cases in CSF cytology, 10 were HER2 negative (IHC 0 or 1+) and two were IHC 2+ in FFPE tissue. Two IHC 2+ cases had HER2:CEP17 ratios of 1.27 and 2.1, respectively, by FISH in FFPE tissue. As a result, the HER2 status concordance rate between metastatic breast cancer cells in CSF and FFPE primary tissue by IHC and FISH was very high. When CSF cytology specimens were appropriately prepared and had adequate cellularity without dry artifacts, the CSF cytology was suitable to evaluate HER2 status by FISH analysis in patients with LM.